Helicopters are commonly used to transport heavy objects by suspending such objects from a cargo hook attached to the helicopter by a cargo line. For example, loads weighing 10,000 pounds or more may be lifted and transported in helicopter logging operations. Such loads impose large vibration forces on the helicopter airframe and on the helicopter's operating personnel. In particular, large vibration forces are transmitted from the load through the cargo line to the helicopter airframe when the load is initially lifted and when it is released. Similar large vibration forces are imposed on the helicopter airframe if the load slips during transport, or if the load inadvertently contacts the ground or some other immovable object during transport.
The present invention provides a vibration damper which may be connected in the cargo line between the load and the helicopter airframe to significantly reduce the vibration forces transmitted to the helicopter airframe.